i don't know if you're backpacking it or doing it as a LONG day hike.
lot's of info here though:
http://www.env.gov.bc.ca/bcparks/exp...robs/berg.html

For Berg lake best to have a reservation if you can get one. It's a busy time of year.

I sometimes like getting up early and driving to the rockies in one shot, the last time we left Fri after work so we dropped in and camped at LacLeJeune just before Kamloops. Depends on your comfort level and how much time you have.

side trip from Berg, I only did Toboggan falls... I was little then and thought it was really cool.

=)